Most vehicle doors provided on a majority of passenger and truck type vehicles include vertically shiftable door latch lock actuators shiftable between upper and lower active and inactive positions, respectively. Further, although it is the usual custom of many drivers to downwardly depress the lock actuator upon entrance into a vehicle thereby providing additonal assurance against unintentional opening of the vehicle door as a result of impact, some drivers and passengers only depress the lock actuators of the doors of a vehicle when exiting from the vehicle in order to prevent the latter from being stolen. Accordingly, in many cases the door latch lock actuators of vehicles are not in the active positions thereof when an accident occurs and the doors of the vehicle are more likely to be jarred open as a result of impact during an accident. Accordingly, many vehicle drivers and passengers are thrown from passenger vehicles and the like as the result of impact during an accident and are more severely injured than they would have been if the doors of the vehicle had not opened on impact and they were thereby contained within the vehicle throughout the accident.
Accordingly, a need exists for a mechanism whereby the door latch lock actuators of passenger vehicles and the like may be automatically depressed in the event of impact. Various types of inertia operated mechanisms have been heretofore designed for this purpose and previously patented devices of this type are disclosed in U.S. Pat. Nos. 2,389,315, 2,864,641, 3,066,964, 3,453,015, 3,719,248 and 3,799,596.